Release Message:  Determined to explore, the Doctor (William Hartnell) leads his companions into the metal city, where they discover the danger of what will become his deadliest enemies, the mutant Daleks.

Description:  The TARDIS lands in a petrified forest on an alien planet. Determined to explore, the Doctor leads his companions into the metal city, where they discover the danger of what will become his deadliest enemies, the mutant Daleks.